Support `prefixItems` for tuple validation about json-schema-to-typescript HOT 2 OPEN

This is a pretty unfortunate change in the spec. It means that the meaning of items is dependent on the version of JSON-Schema you use. But since a JSON-Schema is not required to specify its version, this leaves the interpretation of items ambiguous in practice 🫤.

A middle of the road approach to support this without breaking others' code may be to expose the new behavior behind a switch, say --json-schema-version=2020-12. We would check the option in the normalizer, and normalize prefixItems to items and items to additionalItems if needed.

Want to give this a shot?

from json-schema-to-typescript.

I thought I'd have a go at it.

Added a CLI argument as "--usePrefixItems" which defaults to false, I did not think specifying JSON schema spec version would be helpful at this point since only this version would be supported.

The main addition is a new normalizer rule; renaming the schema keys.

schema.additionalItems = schema.items
schema.items = schema.prefixItems
delete schema.prefixItems

I created a simple unit test as well. I will let it sink in cause maybe more test cases might be needed. I had difficulty understanding the E2E testing setup, so I did not add any new E2E tests, maybe if somebody would very briefly walk me through I am going to do so. Tests are passing, for now.

from json-schema-to-typescript.